In order to evaluate the pre-treatment techniques for reduction and solubility,
microwave, ozone, heat, alkali, ultrasonic, alkali-ultrasonic and alkali-ozone
pre-treatment were investigated. Among the independent use of pre-treatment,
alkali and ozone showed the highest reduction rate and solubility. In reduction
rate, alkali pre-treatment was little higher than ozone pre-treatment. However, in
solubility, ozone pre-treatment was little higher than alkali pre-treatment. Also,
among the incorporative use of pre-treatment, alkali-ozone pre-treatment was the
best pre-treatment for reduction and solubility. At 30 meq/L of NaOH and 0.32
gO3/gSS, the reduction rate and solubility was 39.8 %(VSS) and 41.6 %
respectively in batch test. In continuous test, the reduction and solubility was 10
% lower than in batch test by alkali-ozone treatment.
